There is increasing evidence that labor markets in developed countries are polarizing or hollowing out. On the one hand, the share of employment in high-skilled, high-paying occupations (managers, professionals and technicians) and low-skilled, low-paying occupations (elementary, service, and sales workers) is growing. On the other hand, the share of employment in middle-skilled, middle-paying occupations (clerks, plant and machine operators) is being squeezed. There is ample evidence of polarization in the United States (see Acemoglu and Autor, 2011; Autor and Dorn, 2013; and Autor (2014) for a less technical discussion), and also in Western Europe (Goos, Manning, and Salomons, 2014). Harrigan, Reshef and Toubal (2016), more recently, document the same phenomenon in France, using firm-level data.